﻿<!DOCTYPE html>
<html>
	<meta charset="UTF-8"/>
	<head>
		<script>
			var add = function(){
			
			}
			function add(){
			
			}
			
			
			add();
			
			//编译期间，不执行
			//变量的声明提升
			
		</script>
	</head>
	<body>
		
		<button >点我</button>
	</body>	
</html>











